We currently have a Cisco SG550-48P in our main Data center. Recently we purchased another one for our second campus across town to replace a SG300-28P that is the core at that site. Currently the SG550-48P is connected to the SG300-28P via Single Mode Fiber using a set of MGBBX1/MGBBX1D SFP modules. This has been in place for a little over a year and has worked perfectly. We want to be able to create a horizontal stack between these two sites using the new SG550-48P that we purchased a couple of months ago. I have the 2 Combo ports (XG1 and XG2) configured as the stack ports on the SG550-48P's and have had them stacked using a Cat6 jumper between the 2 switches in the XG1 ports in the Data center and the stack has been up and operational. Yesterday after hours, we took the new SG550-48P switch to site B and moved the MGBBX1/MGBBX1D sfp's and fiber jumpers to the XG1 port on both switches and we cannot get the stack to come up and i do not see any activity on the XG1 ports on either switch. I know the SFP's and fibers are good as if we move them back to the XG4 port on the SG500-48P switch in the Data center and the GE28 port on the old SG300-28P switch, the link comes back up and works perfectly. I have dug through the logs on the SG550-48P and cannot find anything pointing to an issue here. Also, I was wanting to verify there was not something wrong with the SFP port on either of these switches in the XG1/XG2 ports, but cannot find any command or anywhere in the GUI that shows the optical module status for the configured stack ports. Any help would be appreciated.
